Today at Faneuil Hall in Boston, the city's longest serving mayor, Tom Menino, made it official: He is not seeking re-election.

MAYOR TOM MENINO: I'm here with the people I love, to tell the city I love that I will leave the job that I love.

SIEGEL: All that love gives a sense of what drove Menino for nearly 20 years as mayor.

Bruce Gellerman of member station WBUR has this political profile.

BRUCE GELLERMAN, BYLINE: Early this morning, Tom Menino stood in front of his home in the Hyde Park neighborhood of Boston and told reporters after serving as the city's mayor for the past 20 years, he agonized over whether to run for another term.

MENINO: A sad day, but a day that always will come in your career.

GELLERMAN: It was the most difficult decision of my life, says Menino. Not an overstatement for a man who spent his entire life in Boston politics.

JOE TIMILTY: He was a community activist. His first love was politics.

GELLERMAN: Joe Timilty was Tom Menino's political mentor. Menino worked on Timilty's campaigns for state Senate and three unsuccessful runs for the mayor's office.

For Menino, a lifelong Bostonian and longtime member of the city council, all politics was personal.

TIMILTY: Every place he went, he made friends. He worked at it. Nobody gave him anything. He worked at being a counselor. He worked at being a chairman. And he worked at being a candidate. And, you know, you had to have strong relationships.

GELLERMAN: One of his strongest relationships was with Boston Mayor Ray Flynn. Menino, head of the city council, became acting mayor in 1993 when Flynn left office to become ambassador to the Vatican.

TIMILTY: And there was a built-in organization of Ray Flynn people who stayed with him in that fight. And that put him over the top. And, you know, nobody else even came near him.

GELLERMAN: Menino crushed all of his political opponents in five mayoral elections. At times, his popularity in the polls ran over 70 percent. He was mayor when the dot-com bubble burst and when the Red Sox beat the New York Yankees on the way to winning the World Series in 2004 and fans went wild.

(SOUNDBITE OF ARCHIVED AUDIO)

MENINO: A few knuckleheads went too far, and things got out of hand near Fenway Park and other downtown areas. Their outrageous behavior was harmful and disruptive to people who live and work in the Fenway neighborhood.

MIKE BARNACLE: I, actually, was with him one day - I believe it was in Roslindale - stopped the car, get out of the car, look at the Little League field where the grass had overgrown near the infield, go to a pay phone - there were no cellphones then, that's how long he's been mayor - called the Parks Department and got that field mowed. That's who he is.

GELLERMAN: For the past year, Menino has suffered from a series of illnesses. He was hospitalized for two months, only returning home last week.

Some called Tom Menino mayor for life. Back in 1993, when he first became acting mayor, he pledged he'd stay for just two terms. But in 2003, when he ran for a third time, he joked, I meant just two terms a century. He wound up serving five.